Detection of major HBV integration sites in urine as a biomarker for HBV-associated liver cancer This Phase I application is to test the feasibility of using the appearance of major HBV integration sites (the viral-host junction DNA sequences) in the urine of patients infected with the hepatitis B virus (HBV) as a DNA biomarker for the early detection of HBV-associated hepatocellular carcinoma (HBV- HCC). HBV is a major etiological agent that causes more than 50% of hepatocellular carcinoma (HCC) cases worldwide. Despite the availability of a preventive vaccine, chronic hepatitis B infection remains a global health issue, affecting more than 350 million people worldwide, and it is associated with more than 600,0000 deaths annually, most of which are due to the development of HBV-HCC. Although HCC surveillance is implemented for this well-defined, high-risk HBV-infected population, most HBV-HCC remains undetected until late stages by current screening methods, such as expensive ultrasound imaging and the insensitive (~50% sensitivity) AFP blood test. Therefore, there is an urgent need for a more sensitive biomarker for detecting primary and recurrent HCC. The goal of this project is to explore the viability of translating our novel biomarker detection f major HBV integration sites in urine to a noninvasive, urine-based diagnostic test, a UsDx HBV-HCC urine DNA test, that would allow early detection of new and recurrent HBV-HCCs. We have detected HCC- derived genetic and epigenetically modified DNA in the urine of patients with liver cancer. U-Screen Dx, Inc. has performed preliminary experiments that demonstrate the feasibility of this proposal in several key areas. The aims are (1) to develop a target-enriched NGS assay for detecting HBV-host junction sequences (HBV-JS) in urine, and (2) to evaluate the appearance of major HBV-JS in urine as a biomarker for distinguishing HBV-HCC from other liver diseases in HBV-infected subjects. If successful, we will further develop and evaluate the HBV-HCC urine DNA test using clinical samples for the early detection of liver cancer in the high-risk HBV-infected population in Phase II.